Ex-boyfriend mad at me for no reason?

Me and my ex boyfriend broke up 2 months ago, since then we're going ups and downs.We've tried to be friends and somehow it succeeded till now.

We both play League of Legends (a team 5v5 game), we also played with some friends ranked without talking to eachtoher on teamspeak/skype etc. Then he decided yesterday i couldn't play with him anymore (out of the blue) I asked him why i couldn't join.

His answer: Who told you that? I tried to get a clear answer on my question which i still didn't get.He blamed all this friends till i said that i knew it because he posted on twitter a vague 'stop talking bs' tweet. (which he also don't tell me what he means by it)Now he blames me for ruining his 'friendship' and acting like victim.

He deleted and blocked me from everywhere and started to call me bitch all of the sudden on his facebook Before that he kinda stalked my twitter, last fm, kept inviting me to play games with him.

He got even mad when i kicked him from my team last week because he was 'inactive' according to my friends and suddenly he wanted to play more with them. I seriously don't understand this at all..